NBD On-Site service?

I purchase and support laptops for our small business and have had extremely poor support for the past year. When we purchased our laptops, I upgraded to NBD On-Site service. Earlier this year I had a laptop where the motherboard completely died. After diagnosing it on-line, I was told they would setup a support rep to come out the next day to replace it. After I didn't hear from them the next day, I looked up the status of the call and noticed the deliver date was over a week away. So basically if they don't have a part for a warrantied laptop in stock, you don't get NBD on-site service. So you're paying for nothing. I had the same thing happen to me today. I had an 11 month old laptop's video card die. Troubleshot it all yesterday including a Windows reset. They said a tech would contact me today, but when I look at the status of the call, it says the part won't be available until 10/1. Nice. Their products get worse and they have no reason to make sure parts are in stock and yet they still continue to sell NBD On-Site warranties.